SRT Batch Toolkit

Stop processing subtitle files one by one.

SRT Batch Toolkit lets you validate, clean, normalize, swap, and convert entire batches of subtitle files in a single workflow — with deterministic processing and clear reports for every file.

Built for batch subtitle work

Drop in a folder of subtitle files and choose what you need to do.

Validate

Check SRT files for structural and timing issues across an entire batch.

Get clear per-file results instead of manually opening and inspecting every subtitle.

Clean & Normalize

Apply a consistent deterministic cleanup profile across multiple SRT files.

Useful for cleaning subtitle exports before editing, publishing, archiving, or passing them into another workflow.

Swap Bilingual Subtitle Blocks

Reverse the top and bottom text blocks across batches of structurally bilingual SRT files.

For example:

Before

Hello, world.
你好，世界。

After

你好，世界。
Hello, world.

The operation is structural and language-agnostic. It does not rely on translation or language detection.

Convert SRT ↔ WebVTT

Batch convert:

• SRT → basic WebVTT
• basic WebVTT → SRT

Subtitle text and timing are preserved within the supported basic conversion contract.

One bad file doesn't have to stop the batch

Real subtitle folders aren't always clean.

SRT Batch Toolkit reports each item as successful, skipped, or failed, so unsupported or malformed input can be isolated without losing the successful work from the rest of the batch.

A machine-readable manifest makes it easy to see exactly what happened.

Dry-run before processing

Want to inspect the operation first?

Use dry-run mode to evaluate the batch before writing the final output.

Designed for predictable results

This toolkit favors deterministic behavior over guessing.

• No AI language guessing
• No translation
• No silent semantic assumptions
• Per-file results
• Partial failure handling
• Filename collision handling
• UTF-8 and UTF-8 BOM support

Example requests

• “Validate all SRT files in this folder.”
• “Clean and normalize these 50 subtitle files.”
• “Swap the bilingual subtitle blocks in this batch.”
• “Convert all these SRT files to WebVTT.”
• “Run a dry-run first and tell me what will happen.”
• “Process this folder and give me a report of anything that failed.”

Free vs. Batch Toolkit

Need to reverse the two text blocks in a single bilingual SRT?

Use SRT Bilingual Line Swapper for free.

Need to process folders of subtitle files, validate them, clean them, convert formats, or get batch reports?

That's what SRT Batch Toolkit is built for.

Supported in v1

• Batch SRT validation
• Batch deterministic cleanup and normalization
• Batch structural bilingual block swapping
• Basic SRT → WebVTT conversion
• Basic WebVTT → SRT conversion
• Dry-run
• Per-file results
• JSON manifest
• Partial failure handling
• Output filename collision handling

Important limitations

SRT ↔ WebVTT conversion focuses on basic subtitle text and timing. Advanced WebVTT metadata such as NOTE, STYLE, REGION, and cue settings may not be preserved and will be reported when applicable.

ASS/SSA processing and TXT-to-timed-subtitle conversion are not part of the Capafy v1 package.

Legacy encodings such as Big5, Shift-JIS, and GB18030 are not supported.

The bilingual swap feature processes subtitle structure; it does not identify which language each text block contains.

Privacy

Subtitle processing is performed by the packaged local runtime. The toolkit does not require a third-party AI service to analyze, translate, or process subtitle content.